Disaster Management »» Risk Analysis
4.1 INTRODUCTION
Risk is the chance of an event (viz., earthquake, flood or industrial accident) happening that will have negative impact on the society and environment. Risk analysis deals with the systematic use of all available information to determine: (a) how often a specific hazard may occur and (b) the magnitude of their probable consequences. It implies that risk of a disaster is related to: (a) the hazard, (b) the vulnerability of society, structures and the environment to it, and (c) how well the hazards and vulnerabilities are managed.

Risk analysis of an area involves the following steps:
(i) Assess the hazard.
(ii) Vulnerability and Capability Assessment (VCA).
(iii) Quantify the risk.
(iv) Prioritise the actions.

Flood and Earthquake and are considered as the two main natural hazards in Rohtak district Information on the hazard scenario (chapter 3) in the district is used here to calculate the risk.

4.2 RISK ANALYSIS OF ROHTAK DISTRICT
The steps for analyzing the risk posed due to a hazard as mentioned above has been Adopted sequentially for Rohtak

4.2.1 HAZARD ASSESSMENT:
Disaster results from the impact of a hazard, therefore the first step of risk analysis is to assess the hazard. Hazard assessment is concerned with the properties of hazard itself.

1. IDENTIFICATION AND DESCRIPTION OF HAZARD
(I) EARTHQUAKE

Rohtak district falls in Zone IV of Earthquake Hazard Map (Map No.) of India.

(II) FLOOD
Flood is a regular phenomenon in Rohtak. The most flood prone villages in the district are situated. About 55 villages are vulnerable to flooding due to the district’s particular topography.

(B) QUALITATIVE HAZARD ANALYSIS:

4.2.2 VULNERABILITY AND CAPABILITY ASSESSMENT (VCA)

(A) VULNERABILITY ASSESSMENT:
Vulnerability is defined as the degree of loss to a given element at risk resulting from a given level of hazard. Vulnerability analysis (VA) is a process, which deals with the understanding of the types and levels of exposure of persons, property and the environment (against a hazard) at a particular time. This section deals with who and what are exposed to the earthquake. Hence it is clear that information on certain key parameters are essential in conducting VA. While assessing vulnerability of Rohtak, information has been taken from the 1991 census and emphasis has been given on social, economic, housing and environment issues.

(I) SOCIAL VULNERABILITY:
Social vulnerability mainly depends on factors like population density, age, gender and social caste. According to 1991 census, total population in Rohtak was 776966 and population for the year 2001 is 940036. It is seen from map that position and settlement on loose soil make the population of this tehsil more vulnerable to damage due to soil liquefaction, which may follow an earthquake. As the population along this belt is above one lakh , a large number of people are at risk. The district female population is 692779 and it is 48.5 % of total population. The sex ratio in Rohtak is 847 women per 1000 men. The age group also plays a major role in identifying vulnerable groups. The census report shows that age groups of 0 – 14, 15 –19, 50 –59 and more than 60 are more vulnerable than other age groups. Male genders are more vulnerable in 0 –14, 50 –59 and more than 60 age groups. Social caste is also important for identifying the vulnerability of a particular community.

(B) CAPABILITY ASSESSMENT:
Capability (or, manageability) is defined as the degree to which a community can intervene and manage a hazard in order to reduce its potential impact. In indicates the resilience of the community to hazards. Manageability of the community against earthquake at Rohtak have been assessed from the following steps which they take to combat the bad impact of earthquake:

1. AWARENESS
It is observed that the awareness level of the government body and general public is good. The home guards and medical officer in the district have conducted in awareness programmes.

(II) PREVENTION AND MITIGATION MEASURES:
Normally two types of measure viz., structural and non-structural measures are followed. Two conventional methods of mitigation adopted in Rohtak for earthquake are timber framed buildings and seismic huts. In seismic huts, people are residing in masonry or adobe construction houses. Under nonstructural measures, there are no standard practices except some government level insurance to all people in Rohtak

(III) PREPAREDNESS
The rescue and relief plan developed in the guidance of district collector affirms that the Government and the public have already take preparedness measures.

(IV) RESPONSE CAPABILITY
Effort has been made by the district administration to categorize the activities for response. Rescue and relief teams have been constituted under the leadership of an officer - in charge. Police control system, medical relief responsibility and public welfare issues are also explained in the existing Rescue and Relief Action Plan of Rohtak Hence there exists a well-coordinated response strategy among the concerned departments and public.

(V) PUBLIC, GOVERNMENT AND NGO PARTICIPATION:
It has been observed that the teams constituted to carry out rescue and relief operation have representation from Govt., NGOs and public.

(VI) LAWS AND REGULATIONS:
There exists no hard and fast rules and regulations for management of emergency due to natural disasters.

4.2.3 QUANTIFICATION OF RISK:
A simple quantitative method has been adopted to assess the hazard, vulnerability and manageability in Rohtak The methodology has been described as follows:

1. Hazard Assessment of earthquake in Rohtak has been done on the basis of information related to its frequency of occurrence, intensity or severity and its overall impact (Table No. IV). The factors mentioned here for assessment have been categorised as Certain, May occur and Not likely with numerical value of 3,2 and 1, whereas Very, Moderate and Low have been given numerical value of 3, 2 and 1 respectively. The risk due to the hazard calculated from hazard assessment only over Rohtak (as is shown in Table no.IV) is 5/3.
2. Vulnerability assessment in Rohtak against earthquake has been done on the basis of the impact of earthquake on human population, buildings, infrastructures, resources and economy (Table no V). The factors mentioned here for assessment have been categorised as High, Medium and Low with numerical value of 3, 2, 1 respectively.

(c) Manageability assessment for Rohtak has been done by considering the factors viz., overall awareness of the public and Govt., laws and regulation governing this hazard, response capability of Govt. and community, existing procedures of warning or prediction system, prevention and mitigation measures, involvement of NGOs (Table no. VI a &VI b). Poor, Modest and Good with numerical value of 1, 2, and 3 respectively have been considered here to assess the manageability at Rohtak Hence the risk at Rohtak because of earthquake hazard only is calculated as:

4.2.4 PRIORITIZE THE ACTIONS:
With reference to the above mentioned risk analysis methodology adopted for calculating the risk due to an earthquake at Rohtak, it is recommended that the activities to reduce losses should be prioritized. Damages following an earthquake are primarily due to collapse buildings and infrastructures, hence among the activities taken to reduce losses, strengthening of buildings and infrastructure should be taken up a priority. The next priority should be given to further increase the awareness level of the Govt., NGOs and community and also to sustain it.

1. VULNERABILITY

(i) Flood:
The drains have been designed with the formula of 7 cusecs per sq. mile which can be attributed to rainfall of "22 to 25" and the flood waters can be cleared within six days except the pockets/low lying areas of which water can not be dewatered through gravity flow. So it is considered that except these pockets, there will be no damage to the crops in the in the area. It is pertinent to mention that due to continuous flow, irrigation through canals and tube wells, the water table has come up and as a result thereof the crop pattern in the area has also switched to rice mainly from wheat, sugarcane, jawar and bajra. This has also become an additional factor for rise in water table. So the area is prone to floods. The main dewatering process for inhabited area i.e., villages and fields is being taken by the Irrigation Department.

III Preventive Measures:

i) Floods:
The floods can be anticipated, so stress is to be laid for the preventive measures as per saying "prevention is better than cure". So far as Rohtak district is concerned, worse affected has been the Rohtak town itself, because its location is Bowl type i.e., flood watrer has to be dewatered by providing three no. lifts form the jeart of the city. The responsibility to cleat the water rests with the Public Health Department and to make the system more efficient, the various steps such as round the clock electric supply to the pumps by providing alternative feeders, installation of stand by pumps. On the part of Irrigation, the protection of First line and second line ring bund which starts from Rohtak Gohana Railway line up to the Drain No. 8 and then from Hisar Road to Bhiwani Road and further up to Sunaria Road should be well maintained, because as per past history of floods of 1960, the Rohtak town had been victim of Drain No. 8. Though, the drain No. 8 has been rehabilitated and its capacity has been considerably increased by deepening and widening, but regular maintenance particularly clearance of jungle which generally grown is the bed of the drain also as this was the main factor which led to the inundation of Rohtak town by over flowing of drain No.8. Similarly, the worse affected area was during1995, Meham and Sampla due to non maintenance of drains in the area because there was heavy wild growth of patera, kabli kikkar etc. in the bed of pakasma drain due to which there was flooding in Sampla town without heavy rains in the catchment. Similarly, due to non-functioning of link drains in Gohana sub-division i.e., Isapur Kheri link drain, Bhambewa drain and Chhapra drain which outall into the drain No. 8 could not function properly and due to over flow at various points there was unwanted sheet flow in Meham area and worse affected villages were Madina, Mokhra, Behalba, and Nindana. To counteract the floods in the said area, Meham drain, Lakjanmajra drain have been constructed with link drains which untimately outfall into drain No. 8. The proper maintenance of these drains will definitely prevent the floods in the area. In additions to above, the various preventive measures are discussed as under:

Design Criteria for Flood Works:
The drains have been designed with the formula of 7 cusecs per sq. mile which can be attributed to rainfall of "22 to 25" and the flood waters can be cleared within six days except the pockets/low lying area of which water can not be dewatered through gravity flow. So it is considered that except these pockets, there will be no damage to the crops in the area. It is pertinent to mention here that due to continuous flow irrigation through canals and tune wells, the water table has come up and as a result thereof the crop pattern in the area has also switched to rice mainly from wheat, sugarcane, jawar and bajra. This has also become an additional factor for rise in water table. So the area if prone to floods, the main dewatering process for villages and fields is being taken by the Irrigation Department, whereas the dewatering process for villages and fields is being taken by the Public Health Department. The department has excavated number of drains in the area considering the disaster caused by floods of 1995.

Infrastructure of Drains:
To make the district flood-free, the rehabilitation of the existing drains has been done under WRCP while most of the drains have been constructed under NABARD project. During 1995, there was sheet flow between drain No.8 and JLN Feeder which ultimately entered in Rohtak town particularly. To counteract the same, Rohtak drain has been constructed which outfalls into Kultana-Chhudani-Dhupania drain. The latter has also been rehabilitated which outfalls into Najafgarh drain and ultimately the water is discharged kin river Yamuna. The list of the existing drains in Rohtak district is attached as Annexure-I.

3. Protection of Bunds.
The protection bunds are maintained by the Addl. Deputy Commissioner through concerned BD&PO every year. The detail of such bunds block-wise is given in Annexure-II.

4. Dewatering Arrangements and Availability of Material and Manpower.
(a) Irrigation Department:

The availability of pumping, machinery and manpower in the Irrigation Department is as under:
1. Permanent Pump Houses: During the flood season, the primary responsibility of Irrigation Department is to carry out the dewatering of the flood waters affecting village abadies and fields. For this purpose, 10 nos. permanent pump houses having 273 cusec capacity stand installed in order provide relief to the village abadies, live-stock and fields. The list of such pump houses is given in Annexure-III.
2. Mobile Pumps: Besides, some area which is not covered by these pump[ houses, mobile diesel pumping sets having 270 cs. Capacity and electric pumping sets having 630 cs. Capacity are also available in Water Services Mechanical Division, Rohtak for installation at various sites and ring bunds to protect abadies and fields from fury of floods as per site requirement. The list of the availability of mobile pumps is also attached herewithas Annexure-Iv.
3. Temporary Electric Sites to be Installed up to 30.6.
In addition to the above, some temporary electric sites as per list attached as Annexure-IV stand already identified as vulnerable sites where electric pumping sets are installed before 30.6 every year which will functioning as when necessity arises.
4. Deferred Electric Sites: Apart from this, there are some more temporary sites, the installation of which can deferred due to site being approachable but electric connections are to be applied. These sites are to be installed during floods, if required. The list of such deferred sites is also enclosed herewith as Annexure-VI.
In addition to this, some more temporary sites are also installed in the fields according to the intensity of rains and requirement in the fields. So keeping in view the past experience, about 115 nos. electric and 130 nos. diesel sites will be installed in case of floods in the area. The sites to be installed are also depicted on the index plan attached herewith.

B-By Public Health Department:
For dewatering operation within Municipal limit is the responsibility of Public Health Department and for the said purpose, the following pumping sets have been installed:

Main disposal -20 Cs.
Storm disposal -26 "
Harijan Basti -14 "
HUDA complex -60 "
Guru Nanakpura -10 "
Nehru Colony -12 "
Model Town -6 "

Thus a total of 148 Cs. capacity has been installed by the Public Health Department for Rohtak town. With urbanization of the town, the pondage area has also been depleted and the entire quantity of storm water has to be pumped out. The maximum accumulation of storm water takes place in Chhotu Ram Park area. It has a catchment area of 1200 acres and only 60 cusecs of pumping has been installed. Thus in case of 4" of rainfall in a day 300 acre feet of water would be collected and it would take 2 and half days to clear the water.

Pumping Machinery:

The following stand by pumps are also available for dewatering of flood water.

1. Electric Motors Pumping Sets
1. 50 HP 9 Cs. 1No.
2. 35 HP 3.5 Cs. 1No.
3. 35 HP 2 Cs. 3No.
4. 10 HP 1Cs. 1No.

2. Diesel Engine Driven Pumping Sets
1. 100 HP 9 Cs. 1No.
2. 40 HP 5 Cs. 1No.
3. 35 HP 2 Cs. 2No.
4. 10 HP 1Cs. 3No.

(ii) Earthquake:
Earthquake is one of those natural disaster where man, machine and science have failed to forecast the occurrence and intensity of the earthquake. Therefore, preventive measures for ensuring safety of building, structures, communication facilities, water supply lines, electricity and life are of utmost priority.

The Gujrat earthquake has shown that the damage could have been contained or reduced if people had built earthquake resistant houses or taken steps from time to time to strengthen the already built structures. The soil of Rohtak town has a very low load bearing capacity and hence does not have high rise or multi-storeyed buildings. The maximum height allowed both by the Municipal Committee and HUDA is 36 feet or three storeyed buildings. However, since it is an old township there may be several houses, buildings and structures which are about a hundred years old. Immediate steps need be taken to get them vacated and then demolished at an early stage. It is very important to remember that Rohtak district is a very flood prone district and Rohtak town has been badly affected by flood waters several times, the worst being those of 1962, 1983 and 1995 when the town continued to be inundated for several days and in some low lying areas for several weeks. These stagnant waters must have definitely affected the foundation and structure of both old and new houses.

II. Similarly, the Ismaila Railway over-bridge was badly affected by the flood waters of 1995 and the ROB was closed to heavy traffic for several days. The PWD (B&R) authorities may be directed to examine all such bridges and other like structures on the National and State Highways and take measures to strengthening them.

III. The Haryana Urban Development authority has already issued orders making it mandatory for all private builders, contractors and house owners to get certificates from structural engineers regarding the strength of their buildings and al those going in for new constructions will also have to get such certificates before shifting to a newly constructed house.

 
   
   
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